.\" Copyright (c) 2010 Kai Wang
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.\" $Id: dwarf_hasattr.3 3963 2022-03-12 16:07:32Z jkoshy $
.\"
.Dd April 17, 2010
.Dt DWARF_HASATTR 3
.Os
.Sh NAME
.Nm dwarf_hasattr
.Nd check for the presence of an attribute
.Sh LIBRARY
.Lb libdwarf
.Sh SYNOPSIS
.In libdwarf.h
.Ft int
.Fo dwarf_hasattr
.Fa "Dwarf_Die die"
.Fa "Dwarf_Half attr"
.Fa "Dwarf_Bool *ret_bool"
.Fa "Dwarf_Error *err"
.Fc
.Sh DESCRIPTION
Function
.Fn dwarf_hasattr
tests whether the debugging information entry referenced in argument
.Fa die
contains the attribute named by argument
.Fa attr .
Legal values for argument
.Fa attr
are those denoted by the
.Dv DW_AT_*
constants in the DWARF specification.
.Pp
If the named attribute is present in the debugging information entry,
function
.Fn dwarf_hasattr
returns a non-zero value in the location pointed to by argument
.Fa ret_bool .
If the named attribute is not present, a zero is written instead.
.Pp
If argument
.Fa err
is not
.Dv NULL ,
it will be used to return an error descriptor in case of an error.
.Sh RETURN VALUES
On success, function
.Fn dwarf_hasattr
returns
.Dv DW_DLV_OK .
In case of an error, it returns
.Dv DW_DLV_ERROR
and sets argument
.Fa err .
.Sh ERRORS
Function
.Fn dwarf_hasattr
can fail with the following error:
.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
.It Bq Er DW_DLE_ARGUMENT
Either of argument
.Va die
or
.Va ret_bool
was
.Dv NULL .
.El
.Sh SEE ALSO
.Xr dwarf 3 ,
.Xr dwarf_attr 3 ,
.Xr dwarf_whatattr 3
